There is an increasing need for multi-circuit packages for use with electronic assemblies and in the computer industry. As both complexity and miniaturization increases, the need for smaller size, lighter weight packaging and reliability has generated the need for connectors having the ability to reliably connect a large number of electrically conductive traces on closely spaced centerlines in compact areas and particularly between circuitry on parallel surfaces, such as between stacked circuit boards. The requirements of the industry have generated a class of connectors known as elastomeric connectors which can be disposed between circuitry on, for example, a printed circuit board and a glass panel to interconnect corresponding circuits while avoiding the use of solder. The elastomeric member provides sufficient normal force to maintain the electrical interconnection of the circuits yet the member has sufficient compliancy so as not to damage the glass or other panels.
U.S. Pat. No. 4,820,170 discloses one such layered elastomeric connector in which succeeding layers of dielectric material and conductive material are alternated so as to provide a plurality of closely spaced but electrically isolated conductive areas. Typically the elastomeric connector is a rectangular block such that each layer is exposed on all four sides of the block, thus enabling interconnection between circuits on parallel planes or between circuits on planes that meet at essentially right angles. Since the elastomeric connector is compressible and will expand outwardly when subjected to pressure, means must be provided to support the elastomeric block in order to control the direction of expansion and maintain the block in appropriate alignment and to provide dimensioned stability for the block. In using such an elastomeric connector, therefore, a separate support housing or a special cavity within a connector housing is required. These additional parts for providing interconnection add to the number of pieces that must be molded or otherwise formed in order to achieve and maintain the desired interconnection.
U.S. patent application Ser. No. 07/407,762 discloses a panel mounted assembly adapted for interconnecting an electronic package to circuitry on glass panels and the like. The assembly includes a molded electrical connector having a plurality of compliant spring fingers molded integrally with a body portion, the spring fingers including contact means on surface portions that are exposed to be engaged by a mating article. The spring fingers are electrically engageable upon assembling the connector to a corresponding electrical connector having corresponding contact means that are engageable with the compliant spring fingers. The assembly further includes a molded resilient material that provides support for the compliant spring portions and substantial resistance to compression to minimize stress on the corresponding compliant spring portions, thereby resisting the tendency of the polymeric material to "creep" and "stress relax."
When interconnecting circuitry between parallel surfaces, such as in a stacked array of circuit boards, it is generally desirable to have a minimum of space between adjacent boards while maintaining sufficient normal force to assure electrical continuity.
It is also desirable to provide a means for electrical interconnection that requires a minimum of parts.
It is additionally desirable to have an interconnection means that will not damage the surfaces of circuit boards and the like.
It is further desirable to minimize the steps in manufacturing such an assembly.
It is also desirable to have an assembly that is relatively lightweight and compact while maintaining the desired electronic capabilities of the more complex prior art devices.